1. Field of the Invention
The present invention relates to a liquid ejecting apparatus which ejects liquid droplets for recording an image onto a recording medium.
2. Description of the Related Art
Conventionally, an ink jet recording apparatus has been known to include a main tank storing ink, a sub tank storing the ink supplied from the main tank, a recording head configured to jet the ink supplied from the sub tank, a main supply channel communicating between the main tank and the sub tank, and a suction pump provided to the main supply channel. In the abovementioned ink jet recording apparatus, at the time of replacing the ink tank, there is a fear that air may enter into the suction pump through a pipe. When the suction pump is driven in a state of the air entered into the suction pump, since air and ink are stirred intensively, there is a fear that ink which includes a large amount of air bubbles is supplied to the sub tank. Moreover, when the ink flows to a nozzle of the recording head, there is a fear that a jetting failure may occur due to air bubbles.
Further, an ink jet recording apparatus has been known to include an ink tank storing ink, a sub tank storing the ink supplied from the ink tank, a hydraulic head pressure maintaining container storing the ink supplied from the sub tank, and a recording head configured to jet the ink imparted from the hydraulic head pressure maintaining container. In the abovementioned ink jet recording apparatus, at the time of replacing the ink tank, there is a fear that air may enter into connecting portions (joints) and pipes of the ink tank. When air bubbles flow up to a nozzle of the recording head, there is a fear that a blockage of the nozzle may occur due to the air bubbles. Therefore, in the abovementioned ink-jet recording apparatus, the air bubbles and the remained ink are discharged by depressurizing inside of the sub ink tank by a vacuum pump.